Did your try to update PHP to version 7.4, or 8.0. or 8.1 and your website goes down with an http error 500 and the following message?
Fatal error: Uncaught Error: Call to undefined function trailingslashit() in /home/www/public_html/wp-includes/class-wp-textdomain-registry.php:103 Stack trace: #0 /home/www/public_html/wp-includes/l10n.php(784): WP_Textdomain_Registry->set('default', 'it_IT', '/home/www/...') #1 /home/www/public_html/wp-includes/load.php(1401): load_textdomain('default', '/home/www/...', 'it_IT') #2 /home/www/public_html/wp-includes/load.php(162): wp_load_translations_early() #3 /home/www/public_html/wp-settings.php(37): wp_check_php_mysql_versions() #4 /home/www/public_html/wp-config.php(77): require_once('/home/www/...') #5 /home/www/public_html/wp-load.php(50): require_once('/home/www/...') #6 /home/www/public_html/wp-blog-header.php(13): require_once('/home/www/...') #7 /home/ww23xa7a/public_html/index.php(17): require('/home/www/...') #8 {main} thrown in /home/ww23xa7a/public_html/wp-includes/class-wp-textdomain-registry.php on line 103
Please follow the instructions below to fix this error:
- Download the latest WordPress version file and unzip, then replace the folder wp-includes This can fix the problem with the undefined function trailimgslashit().
- Add the line
define ('WP_ALLOW_REPAIR', true);
to the filewp-config.php
. Then openexample.com/wp-admin/maint/repair.php
and follow the steps in the repair dialog to bring back your website.